Select Instance
Merge/Cut from the main menu bar to merge multiple instances of native parts that you created using ABAQUS/CAE. In addition, you can cut a single native part instance using one or more selected native part instances to make the cut. Both operations create a new part instance and a new part. When you merge or cut part instances, you can choose to suppress or retain the original part instances. The merge and cut operations are described in more detail in the following list:
Merge
You can select multiple native part instances and merge them into a single part instance. For example, Figure 13–17 shows two part instances that model a 15-pin connector. The two part instances are positioned along a common face and then merged into a single part instance that can be meshed and analyzed.
If desired, you can use the Part Copy dialog box to create a mirror image of a part about one of the three principal planes. For more information, see “Copying a part,” Section 11.5. You can merge part instances even if the instances are not touching or overlapping. You can choose whether to remove or retain the intersecting boundaries between the merged part instances, as shown in Figure 13–18.You might want to merge part instances for the following reasons:
If part instances touch or overlap but you do not merge them, ABAQUS/CAE creates a separate mesh for each instance and you must apply tie constaints to effectively merge the nodes. In contrast, when you merge part instances, ABAQUS/CAE creates a single combined mesh and you do not need to apply computationally expensive tie constraints. In effect, you have created a compatible mesh between the part instances. If you want to retain the concept of separate part instances, you can create partitions at the common interface of the merged instances.
Merging part instances allows you to assign material properties to the single part created by the merge operation instead of to each part individually.
You can apply a display body constraint to a group of merged part instances instead of applying the constraint to each part instance individually.
When you import a complex assembly, the assembly may appear in ABAQUS/CAE as a large number of individual part instances that will be meshed individually. You can merge all the part instances into a single part instance, or you can merge groups of part instances into several separate part instances.
Cut
You can select a single part instance to be cut, and then you can select one or more part instances that are touching or overlapping the part instance to be cut. ABAQUS/CAE uses the part instances that will make the cut (the die) to cut away from the part instance to be cut (the blank). You cannot cut part instances that are not touching or overlapping.
The cut operation is useful if you want to create a mold from a part or vice versa. Figure 13–19 shows a bottle and a rectangular blank and how the cut process creates the mold.
You cannot make a cut with a shell part instance. As a result, before the cut operation was performed, the bottle was converted from a shell to a solid part in the Part module. For more information, see “Creating a solid from a shell,” Section 47.7.2, . In addition, the original part instances (the blank and the die) were suppressed after the cut operation. The cut operation is also useful for modeling a structure and an acoustic medium when you are performing an acoustic or shock analysis.Note: You cannot merge or cut part instances that contain virtual topology.
